During surgery on organs such as on the heart it is necessary to at least temporarily position the organ. This is important, on the one hand, so that the site of operation of the organ is easily accessible for the operating surgeon. Moreover, especially sensitive organs, as it is the case especially with the heart, must not move during the surgical intervention. Therefore most different technologies and devices for positioning organs during an operation are known.
Organs can be supported and held, respectively, solely by the human hand or with the aid of instruments such as surgical hooks. It is a drawback that in this way an unevenly distributed pressure is exerted on the organ. Furthermore, a position cannot be permanently fixed, especially because the human hand fatigues comparatively quickly and starts twitching. Moreover it constitutes a major visual obstruction.
When drapes are laid underneath, at least the sight of the operating surgeon is unhindered. However, also in this case neither a comfortable nor a permanent positioning is ensured, because the drapes continuously absorb moisture and thus are losing stability. Moreover, the insertion of drapes until the desired position is reached is also time-consuming.
From EP 1 002 498 A1, U.S. Pat. Nos. 5,735,791 A and 6,036,640 A inflatable positioning cushions are known, and from U.S. Pat. No. 4,637,377 A and EP 1 028 656 B1 inflatable wedges are known, wherein the latter document works with a plurality of separate fluid chambers. All of these subject matters are based on the fact that they are put underneath the relevant organ and are subsequently inflated or filled with fluid.
It is a drawback of these systems that they do not take sufficient account of the anatomic conditions of the organs and consequently are not comfortable. Further the non-fitting form results in the fact that the organs have to be clamped, especially in the case of the wedge, and in this way local pressure sores are occurring at the organ, which entails increased hematoma formation. In addition, the hemodynamics of the heart is restricted.
From U.S. Pat. Nos. 6,899,670 B2 and 7,438,680 B2 additionally vacuum-assisted positioning systems are known. These systems substantially consist of a frame to be assembled in advance comprising an arm or jointed arm by which a suction member is mounted on the frame and is positioned at the organ. Moreover, a vacuum pump generates a relative vacuum which is transmitted to the suction member by means of a complicated pressure monitoring apparatus. The suction member sucks the organ and in this way positions the same. It is a drawback that these systems are very bulky. Furthermore they require great mounting efforts before surgery can be started after positioning the organ. Also they are cost-intensive.
The patent document U.S. Pat. No. 5,453,078 A discloses a wedge-shaped sponge means comprising a stiff and absorptive sponge member. The sponge is preferably used to either render the organ to be operated on accessible by pushing organs that bar the way to the side or bringing the organ to be operated on into the operating area. During use the wedge-shaped sponge is clamped between the organs so that upon increasing absorption of moisture it appropriately expands by a multiple of its initial size and clamps the organs.
It is a drawback in this case that the initially stiff sponge exerts an uneven and usually substantially point-shaped pressure distribution on the organ, which is not comfortable and causes hematomas. In addition, an uncomfortable support restricts the hemodynamics of the heart.
In addition, the wedge is brought into a favorable and stable position by trying out so that both the organ is positioned in the desired way and the wedge is safely clamped. This step is time-consuming and even in such case it cannot be excluded that the wedge may come loose again at any time.
Moreover, in the course of continuous soaking of the sponge the state of positioning is continuously varied. It is continuously transformed from a wedged state into a state receiving and partly enclosing the organ. Since in this case the entire pressure distribution changes both between the organ and the sponge and between the sponge and the bearing face, also the positioning of the organ necessarily varies. Accordingly, increasing absorption of moisture is accompanied by decreasing stability of positioning.